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The Influence of Medium on Low-Voltage Circuit Breaker Arcs

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Plasma Science and Technology 2006年第6期8卷 680-684页

作者：杨茜荣命哲 Anthony B.murphy 吴翊 State Key Lab of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'an 710049China CSIRO Industrial Physics Lindfield NSW 2070Australia State Key Lab of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'an 710049China.

This paper mainly focuses on the influence of three kinds of media： air, air-10%PA （Nylon） and air-10% POM （polyoxymethylene） on low-voltage circuit breaker arcs. A threedimensional （3-D） model of arc motioa under the effect of external magnetic field is built based on magnetohydrodynamics （MHD） equations. By adopting the commercial computational fluid dynamics （CFD） package based on the control-volume method, the above MHD equations are solved. For the media of air-10%PA and air-10%POM, the distributions of stationary temperature and electrical potential and the transient motion processes are compared with those of air arc. The research shows that both air-10%PA and air -10% POM can cool the arc plasma and the former is more effective. Both of them can increase the stationary voltage as well. Moreover, the presence of the two mixtures can accelerate the arc motion toward the quenching area and ensures the arc quenched in time.

关键词： arc plasma arc motion thermodynamic and transport properties

Min-Max Theory for Cell Complexes

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Algebra Colloquium 2020年第3期27卷 447-454页

作者： Lacey Johnson kevin Knudson Department of Mathematics University of FloridaGainesvilleFL 32611USA

In the study of smooth functions on manifolds,min-max theory provides a mechanism for identifying critical values of a *** introduce a discretized version of this theory associated to a discrete Morse function on a(regular)cell *** applications we prove a discrete version of the mountain pass lemma and give an alternate proof of a discrete Lusternik-Schnirelmann theorem.

关键词： discrete Morse theory min-max theory

Unconventional routes to developing insect-resistant crops

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Molecular Plant 2021年第9期14卷 1439-1453页

作者： Laramy Enders kevin Begcy Purdue University Department of EntomologyWest LafayetteIN 47907USA University of Florida Environmental Horticulture DepartmentGainesvilleFL 32611USA

Concerns over widespread use of insecticides and heightened insect pest virulence under climate change continue to fuel the need for environmentally safe and sustainable control strategies. However, to develop such strategies, a better understanding of the molecular basis of plant-pest interactions is still needed. Despite decades of research investigating plant-insect interactions, few examples exist where underlying molecular mechanisms are well characterized, and even rarer are cases where this knowledge has been successfully applied to manage harmful agricultural pests. Consequently, the field appears to be static, urgently needing shifts in approaches to identify novel mechanisms by which insects colonize plants and plants avoid insect pressure. In this perspective, we outline necessary steps for advancing holistic methodologies that capture complex plant-insect molecular interactions. We highlight novel and underexploited approaches in plant-insect interaction research as essential routes to translate knowledge of underlying molecular mechanisms into durable pest control strategies, including embracing microbial partnerships, identifying what makes a plant an unsuitable host, capitalizing on tolerance of insect damage, and learning from cases where crop domestication and agronomic practices enhance pest virulence.

关键词： insects plants compatible and incompatible interaction host and non-host plant resista nee

A model of optimising political expenditures to buy government power

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Economic and Political Studies 2019年第4期7卷 433-453页

作者： Austin murphy Department of Accounting and Finance School of Business AdministrationOakland UniversityRochesterMIUSA

This research develops a model of optimal political expenditures and shows how money inevitably controls government leaders,subject only to a single constraint relating to negative public *** paper demonstrates theoretically why many businesses do not make such investments despite abnormally high returns from the expended political *** particular,firms with less economic resources optimally recognise that they can successfully participate in the political process only in consortium with the dominant players of mutual interests to influence broader government *** largest corporations are therefore able to buy government power with a minimal political outlay.

关键词： Lobbying campaign contributions special interests political capital elections investments

High Resolution Global Modeling of the Atmospheric Circulation

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Advances in Atmospheric Sciences 2006年第6期23卷 842-856页

作者： kevin HAMILTON International Pacific Research Center University of Hawaii at Manoa HonoluluHawaii 96822USA

An informal review is presented of recent developments in numerical simulation of the global atmospheric circulation with very fine numerical resolution models, The focus is on results obtained recently with versions of the GFDL SKYHI model and the Atmospheric Model for the Earth Simulator （AFES） global atmospheric models. These models have been run with effective horizontal grid resolution of -10-40 km and fine vertical resolution. The results presented demonstrate the utility of such models for the study of a diverse range of phenomena, Specifically the models are shown to simulate the development of tropical cyclones with peak winds and minimum central pressures comparable to those of the most intense hurricanes actually observed, More fundamentally, the spectrum of energy content in the mesoscale in the flow can be reproduced by these models down to near the smallest explicitly-resolved horizontal scales, in the middle atmosphere it is shown that increasing horizontal resolution can lead to significantly improved overall simulation of the global-scale circulation, The application of the models to two specific problems requiring very fine resolution global will be discussed, The spatial and temporal variability of the vertical eddy flux of zonal momentum associated with gravity waves near the tropopause is evaluated in the very fine resolution AFES model, This is a subject of great importance for understanding and modelling the flow in the middle atmosphere, Then the simulation of the small scale variations of the semidiurnal surface pressure oscillation is analyzed, and the signature of significant topographic modulation of the semidiurnal atmospheric tide is identified.

关键词： general circulation model mesoscale simulation gravity waves atmospheric tides

Novel theoretical constraints for color-octet scalar models

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Chinese Physics C 2019年第9期43卷 1-11页

作者： Li Cheng Otto Eberhardt Christopher W.murphy Institute of Applied Physics and Computational Mathematics Beijing 100094China Instituto de Fisica Corpuscular Universitat de Valencia-CSICApt.Correus 22085E-46071 ValenciaSpain Department of Physics Brookhaven National LaboratoryUptonNew York11973USA

We study the theoretical constraints on a model whose scalar sector contains one color octet and one or two color singlet SU(2)L *** ensure unitarity of the theory,we constrain the parameters of the scalar potential for the first time at the next-to-leading order in perturbation ***,we derive new conditions guaranteeing the stability of the *** employ the HEPfit package to extract viable parameter regions at the electroweak scale and test the stability of the renormalization group evolution up to the multi-TeV ***,we set upper limits on the scalar mass *** results are given for both cases with and without a second scalar color singlet.

关键词： beyond the Standard Model extension of Higgs sector EW symmetry breaking

A near infrared spectroscopy calibration for the prediction of fresh grass quality on Irish pastures

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Information Processing in Agriculture 2022年第2期9卷 243-253页

作者： Darren J.murphy Bernadette O’Brien Michael O’Donovan Tomas Condon Michael D.murphy Teagasc Animal&Grassland Research and Innovation CentreMooreparkFermoyCo.CorkIreland Department of Process Energy and Transport EngineeringMunster Technological UniversityCorkIreland

The aim of this study was to develop near infrared spectroscopy(NIRS)calibrations to predict quality parameters,dry matter(DM,g kg1)and crude protein(CP,g kg1 DM),in fresh un-dried *** of these parameters would enable more precise allocation of quality herbage to grazing *** ryegrass samples(n=1615)were collected over the 2017 and 2018 grazing seasons at Teagasc Moorepark to develop a NIRS calibration *** samples were collected for an independent validation dataset(n=197)during the 2019 grazing *** were scanned using a FOSS 6500 spectrometer at 2 nm intervals in the range of 1100~2500 nm and absorption was recorded as log 1/Reflec*** wet chemistry analysis was carried out for both parameters and the resultant data were calibrated against spectral data by means of modified partial least squares regression.A range of mathematical spectral treatments were examined for each calibration,which were ranked in order of standard error of prediction(SEP)and ratio of percent deviation(RPD).Best performing calibrations achieved high predictive precision for DM(R2=0.86 SEP=9.46 g kg1,RPD=2.60)and moderate precision for CP(R2=0.84 SEP=20.38 g kg1 DM,RPD=2.37).These calibrations will aid the optimisation of grassland management and the development of precision agricultural technologies.

关键词： Near infrared spectroscopy Fresh grass analysis Grassland management Grass quality Precision agriculture

Preliminary studies on the stability of arsenolipids:Implications for sample handling and analysis

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Journal of Environmental Sciences 2016年第11期28卷 97-103页

作者： Muslim Khan kevin A.Francesconi Institute of Chemistry-Analytical Chemistry University of Graz

Human health risk assessments concerning arsenic are now estimating exposure through food in addition to exposure through drinking water. Intrinsic to this assessment is sample handling and preparation that maintains the arsenic species in the form that they occur in foods. We investigated the stability of three arsenolipids（two arsenic fatty acids, As FA-362 and As FA-388, and one arsenic hydrocarbon As HC-332）, common constituents of fish and algae, relevant to sample storage and transport, and to their preparation for quantitative measurements. The fate of the arsenolipids was followed by high performance liquid chromatography/electrospray triple quadruple mass spectrometry（HPLC/ESIMS） *** of the compounds dry as pure compounds or mixed in fish oil at up to 60？C did not result in significant changes to the compounds, although losses were observed by apparent adsorption onto the plastic walls of the polypropylene tubes. No losses occurred when the experiment was repeated with glass tubes. When the compounds were stored in ethanol for up to 15 days under acidic, neutral, or alkaline conditions（each at room temperature）, no significant decomposition was observed, although esterification of the fatty acids occurred at low p H. The compounds were also stable during a sample preparation step involving passage through a small silica column. The results indicate that these typical arsenolipids are stable when stored in glass at temperatures up to 60？C for at least 2 days, and that,consequently, samples of food or extracts thereof can be transported dry at ambient temperatures, i.e. without the need for cool conditions.

关键词： Arsenolipids Stability Mass spectrometry

Global aspirations, local realities: the role of social science research in controlling neglected tropical diseases

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Infectious Diseases of Poverty 2014年第1期3卷 310-324页

作者： kevin Bardosh Centre of African Studies School of Social and Political ScienceCollege of Humanities and Social ScienceThe University of Edinburgh58 George SquareEdinburgh EH89LDUK Division of Pathway Medicine and Centre for Infectious Diseases School of Biomedical SciencesCollege of Medicine and Veterinary MedicineThe University of EdinburghChancellor’s Building49 Little France CrescentEdinburgh EH164SBUK

Neglected Tropical Diseases(NTDs)are both drivers and manifestations of poverty and social *** advocacy efforts since the mid-2000s have led to ambitious new control and elimination targets set for 2020 by the World Health *** these global aspirations represent significant policy momentum,there are multifaceted challenges in controlling infectious diseases in resource-poor local contexts that need to be acknowledged,understood and *** a number of recent publications have emphasised the“neglected”status of applied social science research on *** light of the 2020 targets,this paper explores the social science/NTD literature and unpacks some of the ways in which social inquiry can help support effective and sustainable *** priority areas are discussed,including on policy processes,health systems capacity,compliance and resistance to interventions,education and behaviour change,and community *** paper shows that despite the multifaceted value of having anthropological and sociological perspectives integrated into NTD programmes,contemporary efforts underutilise this *** is reflective of the dominance of top-down information flows and technocratic approaches in global *** counter this tendency,social research needs to be more than an afterthought;integrating social inquiry into the planning,monitoring and evaluating process will help ensure that flexibility and adaptability to local realities are built into *** emphasis on social science perspectives can also help link NTD control to broader social determinants of health,especially important given the major social and economic inequalities that continue to underpin transmission in endemic countries.

关键词： Neglected tropical diseases Applied social sciences Implementation research Social determinants Community participation Policy Global health Sociology Anthropology